scholarly journals Investigation of 8-Aza-7-Deaza Purine Nucleoside Derivatives

Molecules ◽  
2019 ◽  
Vol 24 (5) ◽  
pp. 983
Author(s):  
Hang Ren ◽  
Haoyun An ◽  
Jingchao Tao
Keyword(s):  
Anticancer Activity ◽  
Nmr Spectra ◽  
2D Nmr ◽  
Purine Nucleoside ◽  
X Ray ◽  
2D Nmr Spectra ◽  
Purine Ring ◽  
New Compounds

Glycosylation of 6-amino-4-methoxy-1H-pyrazolo[3,4-d]pyrimidine and its iodo- and bromo- analogues with the protected ribofuranose and 2′-deoxyribofuranose under different conditions resulted in the synthesis of N9- and N8-glycosylated purine nucleosides. Five key intermediate nucleosides, having 6-methoxy, 7-iodo, and 2-bromo groups, were further derivatized to 23 final 8-aza-7-deazapurine nucleoside derivatives. The structures of N9- and N8-glycosylated products were assigned based on UV and NMR spectra. HMBC analysis of 2D NMR spectra and X-ray crystallographic studies of the representative compounds unambiguously verified the connection of ribose ring to N9- or N8-position of the purine ring. The anticancer activity of these new compounds was evaluated.

scholarly journals Reactions of 3-(p-substituted-phenyl)-5-chloromethyl-1,2,4-oxadiazoles with KCN leading to acetonitriles and alkanes via a non-reductive decyanation pathway

2018 ◽  
Vol 14 ◽  
pp. 3011-3017
Author(s):  
Akın Sağırlı ◽  
Yaşar Dürüst
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Synthetic Route ◽  
X Ray ◽  
H Nmr ◽  
2D Nmr Spectra ◽  
Tof Ms ◽  
C Nmr

The present work describes an unfamiliar reaction of 5-(chloromethyl)-3-substituted-phenyl-1,2,4-oxadiazoles with KCN affording trisubstituted 1,2,4-oxadiazol-5-ylacetonitriles and their parent alkanes, namely, 1,2,3-trisubstituted-1,2,4-oxadiazol-5-ylpropanes. To the best of our knowledge, the current synthetic route leading to decyanated products will be the first in terms of a decyanation process which allows the transformation of trisubstituted acetonitriles into alkanes by the incorporation of KCN with the association of in situ-formed HCN and most likely through the extrusion of cyanogen which could not be detected or isolated. In addition, the plausible mechanisms were proposed for both transformations. The structures of the title compounds were identified by means of IR, 1H NMR, 13C NMR, 2D NMR spectra, TOF–MS and X-ray measurements.

scholarly journals Two New Steroidal Alkaloid Saponins from the Whole Plants of Solanum nigrum

2018 ◽  
Vol 13 (11) ◽  
pp. 1934578X1801301 ◽  
Author(s):  
Bui Huu Tai ◽  
Vu Van Doan ◽  
Pham Hai Yen ◽  
Nguyen Xuan Nhiem ◽  
Nguyen Thi Cuc ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Human Cancer ◽  
2D Nmr ◽  
Solanum Nigrum ◽  
Human Cancer Cell ◽  
Human Cancer Cell Lines ◽  
Steroidal Alkaloid ◽  
2D Nmr Spectra ◽  
Whole Plants ◽  
New Compounds

Two new steroidal alkaloid saponins, solanigrosides Q and R (1 and 2), together with four known compounds khasianine (3), solamargine (4), solasonine (5), and soladulcoside A (6) were isolated from the whole plants of Solanum nigrum. The structures of new compounds (1 and 2) were determined by interpretation of HR-ESI-MS, 1D and 2D NMR spectra, and chemical transformation. Compound 4 exhibited potent cytotoxic activity against MDA-MB-231, A549, Hep3B, PC3 human cancer cell lines with IC50 values of 1.86 ± 0.45, 2.24 ± 0.15, 0.78 ± 0.11, 5.13 ± 1.34 μM, respectively.

scholarly journals Two New Compounds from the Leaves of Glochidion obliquum

2016 ◽  
Vol 11 (4) ◽  
pp. 1934578X1601100
Author(s):  
Vu Kim Thu ◽  
Nguyen Van Thang ◽  
Nguyen Xuan Nhiem ◽  
Hoang Le Tuan Anh ◽  
Pham Hai Yen ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Methanol Extract ◽  
2D Nmr ◽  
Chromatographic Methods ◽  
2D Nmr Spectra ◽  
New Compounds

Using combined chromatographic methods, two new compounds, 6β,9β:9,13-diepoxymegastig-4-en-3β-ol (1), 5α,6α-epoxy D:C-friedoolean-8-en-3β-ol (2) were isolated from the methanol extract of the leaves of Glochidion obliquum Decne. Their structures were elucidated by 1D- and 2D-NMR spectra and in comparison with those reported in the literature.

A Green Synthesis and a Chemical Study of the Coumarin, 1-(2-Hydroxy- 2-methyl-2H-chromen-3yl)ethanone

2019 ◽  
Vol 16 (2) ◽  
pp. 128-133
Author(s):  
Emerson Teixeira da Silva ◽  
Ligia Souza da Silveira Pinto ◽  
Solange Maria Silva Veloso Wardell ◽  
James Lewis Wardell ◽  
Marcus Vinícius Nora de Souza
Keyword(s):  
Green Synthesis ◽  
Nmr Spectra ◽  
Chemical Study ◽  
2D Nmr ◽  
Mechanistic Study ◽  
X Ray ◽  
X Ray Crystallography ◽  
General Importance ◽  
2D Nmr Spectra ◽  
Coumarin 1

Coumarins are a class of natural and synthetic products with a wide variety of applications in different fields. Due to the general importance of coumarins, the objective of this work is to further develop the chemistry of 1-(2-hydroxy-2-methyl-2H-chromen-3yl)ethanone, 1, a potentially useful and versatile coumarin but an under-reported compound in the literature. This work describes a green preparation of 1 in the absence of solvents and acids, thereby eliminating byproducts, normally obtained in classical procedures, and a mechanistic study of the reactions of 1 with nucleophiles. In addition, we report the characterisation of 1-(2-ethoxy-2-methyl-2H-chromen-3-yl)ethanone 2, via X-ray crystallography and 2D NMR spectra.

scholarly journals New 3-Hydroxyquinaldic Acid Derivatives from Cultures of the Marine Derived Actinomycete Streptomyces cyaneofuscatus M-157

Marine Drugs ◽  
2018 ◽  
Vol 16 (10) ◽  
pp. 371 ◽  
Author(s):  
Francisco Ortiz-López ◽  
Elsa Alcalde ◽  
Aida Sarmiento-Vizcaíno ◽  
Caridad Díaz ◽  
Bastien Cautain ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Two Dimensional ◽  
Amino Acid Residues ◽  
Trace Level ◽  
One Dimensional ◽  
2D Nmr Spectra ◽  
Ic50 Values ◽  
New Compounds ◽  
Tof Ms

Fractionation of the bioactive extract of a culture of the marine derived actinomycete Streptomyces cyaneofuscatus M-157 led to the isolation of the known 3-hydroxyquinaldic acid (4), its amide (5) and three new derivatives (1–3) containing different amino acid residues. The structures of the new molecules (1–3), including their absolute configuration, were determined by the analysis of their ESI-TOF MS and one-dimensional (1D) and two-dimensional (2D) NMR spectra and advanced Marfey’s analysis of their hydrolyzation products. Compound 3 spontaneously dimerized in solution to give the disulfide derivative 6. Unfortunately, none of the new compounds isolated confirmed the antimicrobial activity found in the bacterial extract, perhaps indicating that such antibacterial activity might be due to presence in the extract at the trace level of larger bioactive 3-hydroxyquinaldic acid derivatives from which compounds 1–3 are biosynthetic precursors. Cytotoxicity tests confirmed the moderate and weak IC50 values of 15.6 and 51.5 µM for compounds 5 and 1, respectively.

scholarly journals A New Aggreceride Analogue and a Peltogynoid Isolated from the Stem Bark of Entada abyssinica (Fabaceae)

2014 ◽  
Vol 9 (10) ◽  
pp. 1934578X1400901
Author(s):  
Raduis Melong ◽  
Deccaux G. F. W. Kapche ◽  
Michel T. Feussi ◽  
Hartmut Laatsch
Keyword(s):  
Nmr Spectra ◽  
Reference Data ◽  
High Resolution Mass Spectrometry ◽  
Optical Rotation ◽  
2D Nmr ◽  
Stem Bark ◽  
Mass Spectrometry Data ◽  
Related Data ◽  
2D Nmr Spectra ◽  
New Compounds

A new monoglyceride, 1′,26′-bis-[( S)-2,3-dihydroxypropyl] hexacosanedioate (1a) and the new peltogynoid, entadanin (3), along with eight known compounds, were isolated from the stem bark of Entada abyssinica (Fabaceae). The structures of the new compounds were determined by detailed analyses of 1D and 2D NMR spectra, in combination with high-resolution mass spectrometry data, and by comparison with related data from the literature. The stereochemistry of 1a was derived by comparison of the optical rotation with reference data. Peltogynoids have been reported previously from other Fabaceae, however this is the first report of a peltogynoid from the genus Entada.

scholarly journals An Imidazopyridinone and Further Metabolites from Streptomycetes [1]

2009 ◽  
Vol 4 (7) ◽  
pp. 1934578X0900400 ◽  
Author(s):  
Hafizur Rahman ◽  
Mohamed Shaaban ◽  
Khaled A. Shaaban ◽  
Muhammad Saleem ◽  
Elisabeth Helmke ◽  
...  
Keyword(s):  
Chromatographic Analysis ◽  
Nmr Spectra ◽  
2D Nmr ◽  
Antibiotic Activity ◽  
Streptomyces Sp ◽  
2D Nmr Spectra ◽  
New Compounds ◽  
Related Compounds ◽  
Resolution Mass ◽  
New Metabolites

Screening and chromatographic analysis of the extracts from the terrestrial streptomycete GW5127 and from the marine Streptomyces sp. isolate B7967 yielded four new metabolites, i.e. 8-ethyl-6,11-dihydroxy-1-methoxy-naphthacene-5,12-dione (1a), 4-acetyl-1,3-dihydro-imidazo[4,5-c]pyridin-2-one (4a), 5-hydroxmethyl-4-hydroxy-2,4-dimethyl-2-cyclopentenone (6), and N-[2-(3′-hydroxy-4′-methoxyphenyl)-ethyl]-acetamide (5a), along with five known compounds, β-rubromycin (2), γ-rubromycin (3), 2-(3′-hydroxy-4′-methoxyphenyl)ethanol (5b), uracil, and N-acetyltyramine. The structures of the new compounds were deduced from high resolution mass, 1D and 2D NMR spectra and by comparison with related compounds from the literature. The antibiotic activity of the crude extracts was due to 2 and 3.

scholarly journals Novel Terpenoids from the New Zealand Liverworts Jamesoniella colorata and Bazzania novae-zelandiae

2010 ◽  
Vol 5 (7) ◽  
pp. 1934578X1000500 ◽  
Author(s):  
Masao Toyota ◽  
Ikuko Omatsu ◽  
Fumi Sakata ◽  
John Braggins ◽  
Yoshinori Asakawa
Keyword(s):  
New Zealand ◽  
Nmr Spectra ◽  
2D Nmr ◽  
2D Nmr Spectra ◽  
New Compounds

Diethylether extracts of New Zealand liverworts Jamesoniella colorata and Bazzania novae-zelandiae were investigated to reveal novel terpenoids. The former extract afforded a new modified clerodane-type diterpenoid, and the latter gave a degraded clerodane (rearranged drimane) type sesquiterpenoid. The structures of those new compounds were established by 2D NMR spectra.

scholarly journals Isolation and Structural Elucidation of Nitrogenous Secondary Metabolites from Terrestrial and Marine Streptomyces spp

2017 ◽  
Vol 12 (3) ◽  
pp. 1934578X1701200
Author(s):  
Mohamed Shaaban ◽  
Khaled A. Shaaban ◽  
Elisabeth Helmke ◽  
Iris Grün-Wollny ◽  
Hartmut Laatsch
Keyword(s):  
Carboxylic Acid ◽  
Nmr Spectra ◽  
Acid Methyl Ester ◽  
2D Nmr ◽  
Benzene Derivatives ◽  
Streptomyces Spp ◽  
Acid Methyl ◽  
2D Nmr Spectra ◽  
New Compounds ◽  
Related Compounds

Screening and chromatography of extracts from a terrestrial and a marine-derived streptomycete yielded two new nitrogenous benzene derivatives, namely ( S)- N-[3-hydroxy-1-(4-hydroxyphenyl)-propyl]-acetamide (1a), and ( R)-2-(1-methyl-2-oxopropylamino)-benzoic acid (2). Additionally, eight known compounds were isolated, 2-acetamidophenol, phenazine-1-carboxylic acid, phenazine-1-carboxylic acid methyl ester, perlolyrin, tyrosol, uracil, and anthranilic acid. The structures of the new compounds were deduced from high resolution mass, 1D and 2D NMR spectra and by comparison with related compounds from the literature. The absolute configuration of 1a and 2 was determined by comparison of experimental and calculated CD and ORD data.

Extensive 1D, 2D NMR Spectra of Some [7.0]Metacyclophanes and X-ray Analysis of (±)-Myricanol

1996 ◽  
Vol 59 (8) ◽  
pp. 759-764 ◽  
Author(s):  
Balawant S. Joshi ◽  
S. William Pelletier ◽  
M. Gary Newton ◽  
Doowon Lee ◽  
Georgia B. McGaughey ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
X Ray ◽  
2D Nmr Spectra
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